INSIDE STORY: Why Oksana Started Recording Mel Gibson's Rants

It was first full day of Lent, and the perfect day for Mel Gibson to gather the people closest to him, including his then-girlfriend Oksana Grigorieva, in a tree planting ceremony to honor his then-2-month-old daughter Lucia at one of his Malibu properties.

“It was supposed to be a celebration,” says a source close to Grigorieva.

Instead, the events of Feb. 18 would result in Grigorieva recording the actor-director-producer’s increasingly disturbing telephone calls to her, recordings that now threaten to permanently unravel his once lofty place in the Hollywood firmament.

So what happened?

“Mel became convinced she was flirting with the gardener, which was completely absurd,” says the source. “But he became enraged about it to the degree that he felt he was a danger to Oksana and the baby.”

A Mother’s Advice

Gibson stormed off his own property in a fury. Grigorieva gathered up the baby and returned to the house in Sherman Oaks, Calif., that Gibson owns and called her mother in Moscow, who had advice for her eldest daughter, according to the source.

“It was her mother who told her she should start recording the calls just in case something happened to her and Lucia,” says the source, who explains that Gibson continued to call Grigorieva’s iPhone throughout that day. “That’s how the recordings started.”

The incident took place more than a month after Grigorieva alleges that Gibson punched her in the mouth and temple on Jan. 6, knocking out one of her veneers and leaving a bruise around her eye. According to the source, Gibson was extremely apologetic after allegedly striking Grigorieva, and she was still emotionally attached to the actor.

A Gibson source previously denied punching Grigorieva, saying he was just trying to prevent her from shaking their baby.

“He actually got down on his knees and begged her for forgiveness, and she decided to go back with him,” says the source. “She was still in love with him.”

She went to the dentist to get her teeth fixed and covered her eye bruise with makeup, says the source. She continued to appear with the actor, even flying with him to his European press commitments for the film Edge of Darkness.

“At that time, all that was on her mind was trying to protect him,” says the source. “She didn’t want anyone to know what he had done.”